Surgical hand support apparatus

Abstract: A surgical hand support apparatus (10) comprising a base block (12) with a finger securing assembly comprising two uprights (22) slidably mounted on tracks (26) defined in the base block, a cross member (48) connected to the uprights. A thumb securing assembly is also slidably mounted to the base block, the thumb securing assembly (60) comprising a standard support member secured to the base block and a hook shaped rod (68) mounted in the standard support member, the standard support member defining a slot (66) through which a post (34) extending from the side of the base block allowing the standard support member and associated hook shaped rod to be reciprocated for selective positioning around the thumb of the patient. A wrist securing assembly (80) is incorporated comprising a plurality of brackets slidably mounted to the base block and a cylindrical cross bar (94) defining a plurality of instrument receiving holes (95) is mounted to the uprights. A lock screw (98) is connected to the cylindrical cross bar to lock the cross bar in place to secure the wrist of the patient and allow selective positioning of surgical instruments with respect to the hand.

Description: BACKGROUND OF THE INVENTION The present invention is directed towards a device for immobilizing a patient's hand while holding the hand on a specially constructed support board in order to facilitate various surgical procedures including endoscopy carpal tunnel release, percutaneous carpal tunnel-plasty and arthoscopy of the hand and wrist. The human hand is the site of a large number of operative procedures and prior art hand restraints have not been able to fully immobilize the hand during a number of surgical procedures. A number of restraint devices have been used to support and restrain a patient's hand for intravenous administration and various surgical procedures. U.S. Patent Number 4,982,744 discloses an immobilizing apparatus including a composite sheet and arm board. The composite sheet includes an adhesive surface on one side and loop fastener on the other side. The arm board includes a fabric hook fastener which engages and holds the hook fasteners of the composite sheet. The patient's hand and/or forearm is secured to the composite sheet by placing the hand and/or forearm on the adhesive surface, the hooked surface of the composite sheet having been previously mounted to the hooked surface of the arm board. A hand belt constructed of fabric loop fasteners, can be used with the restraining device to immobilize the hand. U.S. Patent Number 5,140,998 discloses a surgical hand restrainer device with a flat mitt shaped base member, a spring finger trap and a slidable rigid thumb loop. The spring finger trap is in the form of a mouse trap type spring biased bar and it does not contain any wrist cross bars or guides for the insertion of instruments for performing any operative procedures inside the hand. U.S. Patent Number 3,762,401 discloses a paddle shaped base with a strap hand restraint. The wrist of the patient's hand is held by an optional wrist band and the individual fingers and thumb are held by elastic finger hands. The open wound is held open by a plurality of hooks mounted to a ball and link chain. The chains are mounted to the paddle base by inserting a link in one of a number of notches cut along the periphery of the paddle base. U.S. Patent Number 5,136,743 discloses an apparatus for positioning the distal radioulnar joint for medical examination and is constructed with a platform and a pair of upright blocks mounted on the platform in a spaced relationship to each other. Each of the blocks defines a plurality of slots which hold the posts of plexiglass stabilizing blocks. A post located near the forward end of the platform for selective insertion into anyone of a number of positioning holes cut into the platform provides a gripping surface by the subject. US Patent number 4,370,976 discloses a cast type device made of a soft resilient two piece hinged foam cast which closes together to hold the hand and forearm in a fixed position and is held together by straps. US patent number 4,941,480 discloses a splint for immobilising a patient's arm consisting of a three-sided plastic foam support which is secured to the patient's arm with a series of VELCRO® straps. US Patent numbers 5,025,801; 4,909,264; 4,672,955; 4,453,933; 4,082,257; 3,901,227; 3,476,108; 3,762,401; and 2,266,230; each disclose devices which temporarily restrain or support the hand and/or forearm using straps or bands to secure the hand for surgery or intravenous therapy. The use of straps is disadvantageous in that the straps are difficult to secure and also limit accessibility of the patient's hand and/or forearm. A hand support with the features of the pre-characterising part of claim 1 below is disclosed in US-A-5 029 573. SUMMARY OF THE INVENTION The present invention is defined in claim 1. With the invention, the patient's hand is placed on an inclined support base having a wrist holding assembly and finger securing assembly movably mounted thereon for selective vertical and horizontal adjustment. The assemblies can be secured to the support base by a moveable locking mechanism. The support base is inclined downward from the wrist assembly area towards the finger assembly. The inclined surface of the invention specifically allows instrumentation insertion into the carpal tunnel. A wrist holding assembly is mounted to the support base and may be vertically adjustable thereon. The wrist assembly may be provided with a cross bar which allows catheter guide instruments to be inserted therein for use in operating on the hand. Thus, the present inventive device supports the hand and wrist comfortably for surgical procedures, particularly for minimally invasive hand surgery where instruments are inserted percutaneously or through very small incisions in the hand. The inventive device maximises stability which decreases the fatigue of the surgeon's hands during delicate hand surgery. An assistant is not necessary because the inventive device secures the wrist, hand and fingers and is anatomically contoured for hand surgery, preferably with removable finger separators. It is an object of the invention to provide a custom designed device for conventional hand surgery, endoscopic carpal tunnel release, percutaneous carpal tunnel plasty and arthoscopy of the hand and wrist. For performing percutaneous balloon carpal tunnel-plasty or endoscopic carpal tunnel release, the cross bar on the wrist securing assembly can be provided with a stop guide which protects the groove director guide from migrating downward. The stop guide when the balloon is inflated within the groove director allows the inflation of the balloon to only go superiorly, stretching and dilating the transverse carpal ligament. The underlying median nerve and other structures in the hand are protected throughout the procedure by this wrist securing assembly. It is a further object of the invention to provide for a stop guide which facilitates the introduction of instruments such as grooved balloon guide protectors or an endoscope protecting underlying structures such as nerves, blood vessels and tendons while supporting the hand and wrist during surgical procedures including arthroscopy, carpal tunnel release, open reduction or fixation of fractures. The device can be made radiolucent, facilitating interoperative radiograms for image intensification without moving the hand or wrist during surgery. An optional finger trap device can be incorporated, to maintain finger traction on the digits. The device can be made reusable, and suitable to be autoclaved, it can be made long lasting and suitable for the general handling of delicate tissues required of hand surgery. In the accompanying drawings, there is shown an illustrative embodiment of the invention from which these and other of objectives, novel features and advantages will be readily apparent. BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is a side elevational view of the surgical hand support apparatus with an inserted patient's hand shown in phantom; Figure 2 is a top plan elevational view of the surgical hand support apparatus shown in Figure 1 with the inserted patient's hand and guide director shown in phantom; Figure 3 is a front elevational view of the surgical hand support apparatus shown in Figure 1; Figure 4 is a rear elevational view of the surgical hand apparatus shown in Figure 1; Figure 5 is an exploded view partially in perspective showing the finger separator pins of the base block; Figure 6 is side elevation view of the finger separator pin as shown in Figure 5 inserted into the base block; Figure 7 is a sequential view of the finger separator pin inserted in the base block shown in Figure 6 when the separator pin has been turned and locked into position; Figure 8 is a partially cross sectional view of the track and slide guide mechanism mounted therein used to tighten the finger assembly and the thumb assembly with a portion of the base block removed; Figure 9 is a partial cross sectional end view taken along the track of Figure 8 showing the slide guide mechanism and a section of upright locked into place on the base block; Figure 10 is a perspective view of a catheter guide instrument used in the wrist holding assembly; Figure 11 is a alternate embodiment partial top plan view of the invention using a braided finger holder assembly with the patient's finger shown in phantom; and Figure 12 is a side elevational view of the finger holding assembly embodiment shown in Figure 11. DETAILED DESCRIPTION OF THE INVENTION The preferred embodiment and best mode of the invention is shown in Figures 1-9. The surgical hand support apparatus 10 is designed to hold a hand 200, wrist 201, thumb 202 and fingers 204 in a fixed position for surgery and image intensification. The surgical hand support apparatus 10 is constructed with an inclined plastic base block 12 constructed of a radiolucent plastic material which can be autoclaved. The base block 12 has a planar base rim surface 14 with perpendicular side surfaces 15, front surface 16, rear surface 17 and an inclined hand support surface 18. The base rim surface 14 defines a hollow cavity (not shown) within the base block 12. The inclined hand support surface 18 is cut with an opposite slope of incline 19 from support surface 18 to allow the patient's wrist 201 to be bent backwards with the back of the wrist resting on sloped incline 19 allowing easy entrance of the surgical instrument. The inclined hand support surface 18 is inclined downward from the rear surface 17 to the front surface 16. The planar base surface 14 is provided with a plurality of support feet 13 which keep the block from slipping on the surface on which it is heated. The feet 13 are constructed of a material having a high coefficient of friction such as rubber or plastic. The surgical hand support apparatus 10 is provided with a finger securing assembly 20 as shown in Figures 1, 2, 4 and 5 which incorporates a pair of stainless steel upright side members 22 which are secured to the base block 12 by a slidable locking mechanisms 24. The locking mechanism 24 fits into a "T" shaped channel or track 26 formed by "C" shaped walls 27 of the base block as is most clearly seen in Figure 8. A "T" shaped guide 28 is inserted into channel 26 opening at the front end 16 of the base block with the stem 29 of the "T" shaped guide extending outwardly with its planar base 30 following substantially the same plane as the outer surface of side wall 15 of the base block or being slightly recessed from the outer surface of the side wall. A threaded post 34 is secured to the "T" shaped guide member 28 and extends outward from the base 30 outside track 26 and past sidewall 15 of the base block. A knurled locking nut 36 provided with a stepped locking portion 38 is screwed onto the post 34 adjacent upright side members 22 allowing the finger securing assembly 20 and associated upright side member 22 to slide along the track or channel 26 cut into the base block. The side members 22 are provided with slots 40 through which the post 34 of the locking mechanisms 24 projects. The top of the upright side members 22 are provided with arms 42 having an axially aligned bore 44 cut therethrough. The bore 44 receives the pin 46 as shown in Figure 3. The pin 46 is also inserted through a throughgoing bore 47 cut through each end 49 of cross member 48. Cross member 48 is lowered by sliding upright side members 22 via slots 40 along a respective post 34 to engage the fingers 204 keeping them from moving up or down. The fingers 204 are separated and precluded from lateral movement through the use of finger separation pins 50 which are best shown in Figures 2, and 5 through 7. Finger separating pins 50 are constructed with an oblong handle section 52 tapering to a stepped planar block engaging end 54. A circular post 56 extends from the block engaging end 54, the distal end of the post being provided with an oblong flanged locking section 57. The flange 57 and post 56 are inserted into throughgoing slot 59 cut through the base block 12 into the cavity. The handle 52 is then rotated turning the post and distal end so that the flanged locking section 57 is positioned perpendicular to the slot 59 as shown in Figure 7 keeping the finger pin 50 from being withdrawn. A separate finger separating pin 51 which has the configuration of the pin shown in Figure 6, a circular post with no flange is placed in circular aperture 58. This pin is easily removable and is put in after pins 50 have been locked into position to hold fingers 204 in a fixed lateral position. As noted, the construction of pin 51 is the same as pin 50 differing only in that pin 51 does not have flange 57. There are three series of finger separating holes cut into the base block, two outside sets of oblong slots 59 and a center set of round holes 58. These holes provide maximum flexibility to stop or limit lateral movement of any size hand. A thumb securing assembly 60 is slidably mounted to side 15 of base block 12 in the same manner as the finger assembly 20 to hold thumb 202 in place during surgery. The locking mechanism 24 is constructed of a threaded side post 34 secured to base 30 of the "T" shaped guide 28. The side post 34 receives a knurled lock nut 36 with stepped locking portion 38 to hold a slidable support member 64 in a fixed position or can be unscrewed allowing the thumb assembly 60 to be moved to a selected position. The slidable support member 64 which has a rectangular configuration is provided with a slot 66 cut along its length which allows the side post 34 to be inserted therein allowing support member 64 to be selectively positioned by sliding it via slot 66 along side post 34 and along track or channel 26. The slidable support member 64 also defines a throughgoing bore 65 which holds a curved thumb containment hook 68 in a fixed position. The thumb containment book 68 is formed with a straight section 69 allowing the containment hook to be inserted in the throughgoing bore 65 with the other end of the thumb support hook being bent or curved at 70 which allows the curved end to be rotated over and around thumb 202. A knurled locking knob or nut 36 is threaded on the side post 34 to secure the slidable support member 64 causing the same to be held in a fixed position after the desired vertical placement of the curved thumb containment hook with relation to the thumb 202 is obtained. A wrist holding assembly 80 as best shown in Figures 1, 3 and 6 is mounted to the base block 12. The wrist holding assembly is constructed with two upright brackets 82 mounted on each side of the base block, each bracket defining an adjustment slot 84 and a cross member aperture 86. One of the bracket uprights is provided with an integral locking seat 87 which extends outward perpendicular to the bracket surface. As shown in Figure 1, a locking knob 88 is mounted on threaded post 90. A threaded post 90 is secured in each side 15 of the base block 12 and extends through the adjustment slot 84 of upright bracket 82. The stepped locking end 89 of the locking knob 88 engages the outer surface of the upright bracket 82. The locking knob 88 is rotated, screwing the same on threaded post 90 so that stepped end 89 of the locking knob 88 abuts against the upright bracket 82, locking it into the desired vertical position against the base block 12. A cylindrical tool holder and wrist restrainer bar 94 is mounted through the apertures 86 in the upright brackets 82 and is supported by the upright brackets 82. The holder and wrist restrainer bar 94 defines a plurality of throughgoing bores 95 having a diameter sufficient to hold a catheter director or guide 300, which is shown in phantom in Figures 1 and 2, and in perspective in Figure 10, in the desired position for the surgery. The holder and wrist restrainer bar 94 also is provided on one end with a locking screw support nipple 96 having a threaded throughgoing bore 97 in which a locking screw 98 is threaded. The locking screw 98 is aligned so that it is adjacent the locking seat 87 and is screwed against the locking seat 87 keeping the bar 94 from rotating. The locking seat member 87 is screwed onto the upright bracket 82 with set screws which are recessed in throughgoing bores cut through the upright bracket 82 into threaded blind bores cut into the locking seat member 87. The other end of the holder bar 94 has a threaded post 93 which receives knurled limit end knob 99 to keep the holder bar from being pulled or slid out of the upright bracket 82. The bottom of end of each upright 82 is formed with a boss or end portion 100 having a throughgoing bore 101. The boss bore 101 is axially aligned with bores 102 cut in yoke arms 103 of a bottom cross member 104 to received holding pin 105 holding the bottom cross member 104 to the bottom of upright 102. The bottom cross member 104 has a throughgoing aperture 106 which receives the end and forms a seat for a threaded elevator screw 107. The elevator screw 107 is thus secured to bottom cross member 104 and extends into base block 12 adjacent rear wall 17. The elevator screw 107 which is fixed in place and does not turn holds a threaded insert 108 which is moveably mounted on the elevator screw and rotatably mounted in elevator block 109. The elevator block 109 is placed into a reverse "T" or hat shaped cut out 110 cut into the rear wall 17 of the base block 12 and is screwed to the base block with four set screws C (not shown) extending up through the rim into the base block. When the knurled handle 112 of insert 108 is rotated, the wrist holding assembly 80 and instrument guide cross member 94 moves or is driven vertically upward or downward to provide for vertical positioning of wrist holding assembly. An alternative embodiment of the finger support assembly is shown in Figures 11 and 12. In this finger support assembly 120 "L" shaped standards 122 are slidably mounted in a track 26 via the guide mechanism 24 previously discussed and a secondary post 123 which screwed into the standard 122 by screw 125. One arm 124 of the "L" shaped standard holds the sliding and guide mechanism 24 and the other arm 126 holds a finger support bar 128 having an oblong cross section. The finger support bar 128 is provided with threaded posts 130 on each end which are inserted through a throughgoing bore 127 cut in arm 126 to receive a knurled stepped locking knob 132. The knurled locking knob has a stepped locking portion 133 which engages the outer surface of the "L" shaped standard when it is threaded onto the respective post 130. The finger support bar 128 is provided with a plurality of throughgoing bores 129 which can selectively hold one or more finger holding mechanisms 134. Each finger holding mechanism 134 is constructed with a circular post 135 having a yoke 136 at one end with the other end of post 138 being threaded. The yoke 136 holds a cup member 140 with a threaded pin 141, the cup member holding securely therein braided wire finger locks 142 commonly known as a Chinese finger locks. The finger locks 142 are compressed to receive a finger and allowed to expand after the finger is in place so that attempted removal of the finger results in stretching thus holding the finger in the finger lock. The threaded post end 138 has a knurled driving nut 144 which engages the rear surface of the finger support bar 128 allowing the finger locks 142 to be transported laterally with respect to the top surface of the inclined block. Thus, the patient's fingers 204 are inserted into the finger locks 142 so that the respective finger 204 is inserted up into the compressed braided wire lock 142 at which time the compressed braided wire is relaxed and allowed to expand tightly holding the fingers. When the wrist restraint assembly 80 is placed in position, the fingers 204 are hold in a locked position and the finger locks 142 can be tightened or loosened by movement of the locking nut 144 driving the finger locks 142 toward or away from the patient, thus, keeping the patient's fingers in a selected tensional fixed position. When the device 10 is being used in an operation, the patient's hand 200 is laid on the inclined surface 18 of block 12 with the fingers 204 placed on the lower part of inclined surface 18 and the wrist on the upper part of the inclined surface 18 projecting downward on slope 19. The finger support bar 48 and connected upright side members 22 are then slid along tracks 26 cut into the base block 12 via locking mechanism 24 and its associated guide 28 until the bar 48 is positioned over the fingers 204. The finger support bar 48 is then slid downward along slots 40 in upright side support members 22 until it engages fingers 204. Tensioning knobs 36 are threaded onto rotated on each respective center post 34 until the planar base 37 of the stepped portion 38 engages the outer surface of the upright side member 22 locking the finger securing assembly 20 into a fixed position on the block 12 engaging the finger 204. Pins 50 have been previously mounted and locked in holes 59 of the base block to limit lateral movement of the fingers and middle pin 51 is inserted into aperture 58 the base block 12. The thumb assembly 60 is then engaged with the patient's thumb 202 by sliding the hook member 68 and its associated support member 64 upward, and sliding support member 64 downward until the bottom of hook 68 engages the thumb 202 holding it against the surface 18 of block 12. The locking knob 36 is then rotated to hold the support member 64 and thumb hook 68 in a fixed position. The wrist restraining bar 94 is then inserted through bores 86 in the bracket uprights 82 and the limit knob 99 is screwed into the end of the wrist restraining bar. Adjustments can be made by turning the elevator adjustment knob 112 which raises and lowers the wrist holding assembly 80 in relation to inclined surface 18 until the wrist restraining bar 94 engages the wrist. The bracket uprights 82 are then locked into position by screwing locking knobs 88 into threaded post 90 so that the stepped end 89 of locking knob 88 abuts against the external surface of bracket upright 82 holding it in a fixed position against block 12. Locking screw 98 is screwed into locking seat 87 holding the restraining bar 94 in fixed position for insertion of surgical instruments. Necessary surgical instruments such as guides 300 as shown in Figure 10 can be inserted through bores 95 against the hand 202 at which time surgery commences. The claims which follow identify embodiments of the invention additional to those described in detail above.

Claims: A surgical hand support (10) comprising a base block (12) adapted to support a patient's hand (200), said base block defining an inclined surface (18) for supporting the hand during surgery, the distal end (16) of the inclined surface being lower than the proximal end (17) of the inclined surface to incline downwardly away from the patient's wrist (201) towards the patient's fingers (204), and a finger securing assembly (20) for attachment to said base block, the hand support being characterised in that: the finger securing assembly includes a cross member (48, 128) for restraining the patient's fingers from moving up and down, said cross member being movable towards and away from the inclined surface and also being movable in the length direction of the inclined surface; and further characterised by: a movable wrist securing assembly (80) mounted to said base block and comprising a surface (95) to hold a surgical instrument in a desired position for surgery on the hand. An apparatus as claimed in claim 1 wherein said cross member is provided as a crossbar, and said finger securing assembly comprises a pair of upright members (22) slidably mounted to said base block, one at each end of the crossbar, and with the cross bar mounted to said uprights. An apparatus as claimed in claim 2 wherein each of said finger securing assembly upright members defines a slot (40), a removable side post fastening mechanism movably mounted in a channel (26) defined by said base block, said side post fastening mechanism comprising a guide member (28) and a side post (34) extending from said guide member through said upright member slot and fastening means (36) fastening said upright member in a fixed position. An apparatus as claimed in claim 1, 2 or 3, further comprising track means (26) formed in said base block, said finger securing assembly being mounted in said track means. An apparatus as claimed in any one of the preceding claims, wherein said wrist securing assembly (80) is rigid and includes a plurality of bracket members (82), a cross bar (94) mounted in said bracket members and locking means (98) connected to said cross bar to lock said cross bar in place, said rigid wrist securing assembly movably mounted to said base block to selectively assume a desired vertical position with respect to the surfaces of said base block. An apparatus as claimed in claim 5 wherein said cross bar defines a plurality of apertures (95) therein allowing an instrument guide to be placed therein. An apparatus as claimed in claim 5 or 6, further comprising elevator means (84) connected to said bracket members of said wrist assembly to move said bracket members and associated cross bar relative to said base block to a selected vertical position. An apparatus as claimed in any one of the preceding claims, further comprising a thumb securing means (60) movably mounted to said base block. An apparatus as claimed in claim 8, wherein said thumb securing means further includes a support member (64) and fastening means (36) mounted to said base block allowing said support member to be moved to a selected position in two orthogonal axes and then fastened in a fixed position. An apparatus as claimed in claim 9 wherein said fastening means comprises a guide member (28) mounted in a track (26) formed in said base block, a threaded post (34) extending outward from the guide member, a slot (66) in the support member, and means (36) meshably releasably to clamp the support member in a chosen position along the slot and in a chosen position of the guide member along the track. An apparatus as claimed in any one of the preceding claims further comprising removable pin means (50) selectively mounted in a plurality of bores (58, 59) defined in said base block, said pin means extending from said base block inclined surface to separate and limit lateral movement of the patient's fingers. An apparatus as claimed in any one of the preceding claims further comprising a braided finger retainer means (142) positioned on said base block and adapted to engage the patient's finger.

Inventors: BERGER J LEE, BERGER, J., LEE
Applicants: BERGER J LEE, BERGER, J., LEE
Application year: 1994
Main classification: A61G13
IPC codes: A61B17, A61G13